Mold jacket



Marsh 18, 1941. D. A. COLLKNGS MOLD JACKET Filed Aug. 24, 1938 INVENTOR.Day/dd. CoZ/myks: B 0 g 0 w%/ I ATT RliYf rigid accuracy,

Patented Mar. 18, 1941 PATENT OFFICE MOLD JACKET David A. Collings,Cleveland, Ohio, assignor to Hazel K. Hines Application August 24,1938,Serial No. 226,503

I 5 Claims.

This invention relates to a mold jacket and method of making same and isparticularly directed to a jacket having corners entirely open butresiliently connected. The present jacket departs from the twopreviously known practices of either having a jacket entirely rigid orhaving the sides mutually entirely loose within certain limits. Here thejacket is held to a firm and accurate relation of the sides, just as inan absolutely rigid jacket, and this relation is maintained as long as adefinite degree of stress is not exceeded. When this stress is exceeded,the sides move relatively to one another. In. other words, although thejacket is initially made to the corner connections are springssumciently stiff to maintain the basic size of the jacket, but allow thesides to spread beyond such basic dimensions, and to conform themselves,within limits allowed by the resilient connections, to being placedhigher up or further down on a sloping sided sand mold.

To the accomplishment of the foregoing and related ends, said invention,then, consists of the means hereinafter fully described and particularlypointed out in the claims.

The annexed drawing and the following description set forth in detailcertain structure embodying the invention, such disclosed meansconstituting, however, but one of various structural forms in which theprinciple of the invention may be used.

In said annexed drawing:

Fig. l is a perspective view of my improved jacket;

Fig. 2 is a side elevation;

Fig. 3 is a corner detail looking downward and omitting the taper forsimplicity;

Fig. 4 is an elevation of a fastening detail, showing the face which inassembly goes against the jacket side;

Fig. 5 is a plan view of the drag half only of a molding jig for use inthe manufacture of the corner fastenings; with the fastenings sectionedon the plane 55 of Fig. 7;

Fig. 6 is a vertical section on the plane 6-6 of Fig. 5; and

Fig. '7 is a vertical section on the plane I-I of Fig. 6.

The description and illustrations of my improved jacket are on a basisof the conventional 4-sided mold jacket, but it will be understood thatthe principles are applicable with jackets with a different number ofsides.

As shown in Fig. 1, the jacket comprises separate end slabs I, I andside slabs 2, 2, all generally designated by the word Sides, Spaced atthe ends so as to give the jacket open corners, and connected at suchcorners by stiff strap springs 4 of approximately L-shape with reentrantends, such ends being embedded in fastening pads or escutcheon plates 5which may conveniently be of approximately triangular outline and towhich the slabs I and 2 are bolted or riveted as at I2. These pads arepreferably cast on the ends of the spring, but it will be-apparent thatother mechanical arrangements may be used for the same purpose.

Where so cast, the casting may be accomplished by a permanent mold orcastingjig II), Fig. 5, with mold cavities I I in which the reentrantends 6 of the spring 4 are held.

The pads 5 are cast on at the correct angle by means of the permanentmold or casting jig shown in Figs. 5, 6 and 7, wherein it will beobserved that the mold cavity II is inclined from the vertical at anangle equal to the angle of the slabs I and 2. As illustrated in Figs. 5and 6, this permanent mold comprises a drag I5 and cope IS with a gateI! for each mold cavity and is illustrated with a casting therein andsectioned.

Since all the corners are made in the same permanent mold, the innerface of every pad has the same angle (as 5) and thus when the cornerfastenings are bolted or riveted onto the pads, the pad facesnecessarily set them and keep them at the intended angle (say 5) to thevertical.

When the jacket is placed on a sand mold of precisely the jacketdimensions and not forced down thereon, it acts as a rigid jacketbecause the corner springs are stiff enough not to deflect readily.

If the mold is of such a character that the outward pressure of themolten metal is expected to be greater than the force necessary to bendthe undistorted springs, the jacket can be forced further down on themold, spreading the sides and putting additional tension on the springs,thus adding to the compressive effect of the jacket on the mold.

The jacket is normally intended to be used on molds of the sameinclination as its own sides, but can be placed on molds having faces ofother inclinations and conform thereto if the sand of the molds issufficiently hard and dense not to be injured by the torsional effect.

Inasmuch as the flask is entirely open at the corners the vexingproblems of making the jacket corners fit accurately upon the corners ofthe mold is entirely avoided, but the unsupported span of sand at thecorners is not great enough to allow the metal to break out.

Adjustable jackets with loose hinges at the corners have sometimes beenused, but the difficulty with these is that their sides are not firmlyheld to any basic angles or dimensions, and furthermore, when the limitsof play allowed by the looseness are reached, binding occurs. This isavoided in my invention because the ends of the slabs are not at anytime in contact, nor are there any attachments to the ends which comeinto contact. The slabs of my jacket are always held apart by the spring4 so that there can never be any binding of rigid parts, or anyconcentration of load at a pinching point. Thus danger of breakage isminimized and there can be no binding.

Each side, with its fastening pads, forms a rigid element, just asthough the pads and the slabs were integral. The interior faces of thepads are of substantial area so that they firmly position the slabs inthe assembly at the correct angle, while the stiffness of the springsassures accurate dimensions from end to end and side to side of thejacket. The effect is of four slabs held entirely out of contact but ina definite spaced relationship both as to dimensions and angles, andeach connected to the next only by a single and simple spring ofsufficient rigidity to maintain the relations of the sides in ordinaryhandling.

Other modes of applying the principle of my invention may be employedinstead of the one explained, change being made as regards the structureherein disclosed, provided the means stated by any of the followingclaims or the equivalent of such stated means be employed.

I therefore particularly point out and distinctly claim as my invention:

1. A foundry jacket comprising a plurality of walls arranged in apolygonal structure having open corners, and spring connections betweenadjacent wall ends bridging each corner, said connections including apad formed on each end of each spring, said pad having a face secured toits respective wall end normally to fix the angular relation between thewall to which secured and the adjacent wall.

2. A foundry jacket comprising a plurality of slabs arranged to form apolygonal structure, the end of each slab being spaced from the adjacentend of the next slab, a spring at each corner bridging such space andpads molded on each end of such spring with the inner faces of said padsin fixed angular relation to each other when the spring is not stressed,said springs being separate at each corner, said pads being secured withtheir inner faces against the backs of said slabs, whereby said angularrelation of said pad faces fixes said slabs in a corresponding normalangular relation.

3. A foundry jacket comprising a plurality of walls arranged to form apolygonal structure having open corners, and spring connections betweenadjacent wall ends bridging each corner, said connections comprising aspring having ends defining a plane and a pad cast on each of said ends,said pad having an inner face secured to the back of its respective wallnormally to fix the horizontal and vertical angular relation between thewall to which it is connected and the adjacent Wall.

4. A foundry jacket comprising a plurality of walls arranged to form apolygonal structure having open corners, and spring connections betweenadjacent wall ends bridging each corner, said connections comprising aflat spring and a pad cast on each end thereof, said pad having an innerface secured to the back of its respective wall normally to fix thehorizontal and vertical angular relation between the wall to which it isconnected and the adjacent wall.

5. A foundry jacket comprising a plurality of walls arranged to form apolygonal structure having open corners, and spring connections betweenadjacent wall ends bridging each corner, said connections comprising aspring having ends directed reversely to and inwardly of the mainportions thereof, and a pad cast upon each said end, said pad having aninner face secured to the back of its respective wall normally to fixthe horizontal and vertical angular relation between the wall to whichit is connected and the adjacent wall.

DAVID A. COLLINGS.

